java - Is it possible to find an image file extension from its byte array contents? -

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इस सवाल का पहले से ही एक उत्तर है: < / P>

  • 3 उत्तर

पहले से संग्रहीत एक छवि फ़ाइल होने बाइट सरणी के रूप में एक डेटाबेस में, क्या बाइट सरणी सामग्री से छवि फ़ाइल एक्सटेंशन खोजना संभव है?

मैं डेटाबेस से बाइट सरणी प्राप्त कर सकता हूं मुझे छवि फ़ाइल को स्क्रीन में दिखाने की आवश्यकता है।

इसे प्रदर्शित करने से पहले, मुझे छवि फ़ाइल एक्सटेंशन, जैसे कि .png , .jpg या .jpeg , आदि।

अधिकांश फ़ाइल स्वरूपों में एक "मैजिक नंबर" की शुरूआत में कुछ बाइट्स के रूप में जो इंगित करता है कि यह फ़ाइल क्या है।

GIF "GIF89a" या "GIF87a" से शुरू होता है, यानी बाइट 47,49,46,38, जेपीईजी एफएफ, डी 8 के साथ शुरू होता है और एफएफ, डी 9 के साथ समाप्त होता है

पीएनजी 89 से शुरू होता है, 50,4 ई, 47,0 डी, 0 ए, 1 ए, 0 ए

मैजिक नंबर के बारे में अधिक देखें

अन्य प्रारूपों के लिए आप जादुई नंबर को Google कर सकते हैं कुछ के पास कोई भी नहीं है।


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